Power is a problem with most electronic systems and in particular with memory systems. The continued scaling of CMOS technology has caused standby power dissipation of SRAMs to become an increasing problem. Six transistor (6T) SRAMs are considered one of the lowest power CMOS circuits and thus power loss is particularly important in these devices.
As larger and larger caches are integrated on a same die, the total transistor width allocated to cache increases. At the same time, the transistor leakage per unit width increases with the scaling of technology. Accordingly, the cache is consuming a larger and larger percentage of power.